难溶于二甲亚砜多糖的甲基化方法研究

METHYLATION OF POLYSACCHARIDES UNDISSOLVED IN DIMETHYL SULFOXIDE

本文对难溶于二甲亚砜 (DMSO)但易溶于水的多糖———羊栖菜褐藻糖胶的甲基化方法进行了研究。10mg多糖用 0 1mL水溶解后 ,加入 3mLDMSO ,使多糖转溶于DMSO ,然后加入 2mL 3A分子筛脱除水分。将DMSO溶液过滤后 ,滤液中加入 5 0mgNaOH粉末 ,室温下反应 10min。加入 0 5mL碘甲烷 ,室温下反应 6 0min。加 1mL水终止反应 ,加 1mol/LHAc中和、透析、冻干。该法简便易行 ,所得产物的甲基化程度比较高。

Methylation of fucoidan from brown seaweed Sargassum fusiform,which was undissolved in dimethyl sulfoxide (DMSO) but dissolved in water,was studied.Polysaccharide sample (10 mg) was dissolved in water (0.1 mL),followed by adding DMSO (3 mL).Then the 3A molecular sieves (2 mL) was added to remove the water left in DMSO.After filtering the DMSO solution,powdered dry NaOH (50 mg) was added to the filter liquor.The mixture was sonicated at room temperature for 10 min,followed by adding methyl iodide (0.5 mL).The mixture was sonicated at room temperature for 60 min,mixed with water (1 mL),neutralized using 1 mol/L HAc,dialysed against water,and lyophilized.The method is simple and easy.The methylation degree of the product is high.